The invention relates to a weighing device, e.g. for kitchens. It has a support plate (1) for receiving the object to be measured and a controller (16). Furthermore, an excitation element (12) for generating mechanical vibrations in the support plate (1) and a measuring element (14) for measuring the mechanical vibrations of the support plate (1) are provided. The excitation element (12) and the measuring element (14) are used to determine one or more resonance frequencies and/or other spectral characteristics of the support plate (1), and this is used, for example, to determine the mass of the object.

A load sensor and load detector for detecting the weight of tiny substances such as viruses or bacteria and includes a resonance generator causing a vibrating unit to resonate, a load sensor, and a voltage detector that detects change in induced electromotive force in a pick-up. The load sensor includes the vibrating unit, pick-up, and a substance adsorbent. The vibrating unit includes a magnetostrictive element capable of resonating. The pick-up generates an induced current using inverse magnetostrictive effect of the magnetostrictive element resulting from the vibrating unit vibrations. The substance adsorbent is provided at the vibrating unit, is composed of an antibody to viruses or bacteria and at least partially covers the vibrating unit. The pick-up is composed of a coil with the vibrating unit arranged inside the coil. The vibrating unit is formed by bonding the magnetostrictive element and a soft magnetic body to each other.